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A370555
a(n) is the numerator of f(n)*conj(f(n)), where f(n) = Product_{k=1..n} (1/k + i), i is the imaginary unit, and conj(z) is the complex conjugate of z.
2
2, 5, 25, 425, 221, 8177, 204425, 13287625, 544792625, 2200962205, 134258694505, 19467510703225, 9791351537125, 1928896252813625, 8718611062717585, 2240683043118419345, 1124218135820660225, 365370894141714573125, 66132131839650337735625, 1060759394707991417279425
OFFSET
1,1
COMMENTS
f(n) may also be chosen as Product_{k=1..n} (1 + i/k) without changing the result.
PROG
(PARI) a370555(n) = my (f(n)=prod(k=1, n, 1/k+I)); numerator(f(n)*conj(f(n)))
CROSSREFS
A370556 are the corresponding denominators.
Sequence in context: A378327 A191951 A356674 * A120767 A051771 A008318
KEYWORD
nonn,frac,easy
AUTHOR
Hugo Pfoertner, Feb 23 2024
STATUS
approved